[PATCH v2] perf annotate: Fix s390 target function disassembly

[PATCH v2] perf annotate: Fix s390 target function disassembly

[Thomas Richter]

Perf annotate displays function call assembler instructions
with a right arrow. Hitting enter on this line/instruction
causes the browser to disassemble this target function and
show it on the screen.  On s390 this results in an error
message 'The called function was not found.'

The function call assembly line parsing does not handle
the s390 bras and brasl instructions. Function call__parse
expects the target as first operand:
	callq	e9140 <__fxstat>
S390 has a register number as first operand:
	brasl	%r14,41d60 <abort>
Therefore the target addresses on s390 are always zero
which is an invalid address.

Introduce a s390 specific call parsing function which skips
the first operand on s390.

Signed-off-by: Thomas Richter <tmricht@linux.vnet.ibm.com>
---
 tools/perf/arch/s390/annotate/instructions.c | 53 +++++++++++++++++++++++++++-
 tools/perf/util/annotate.c                   |  2 +-
 2 files changed, 53 insertions(+), 2 deletions(-)

diff --git a/tools/perf/arch/s390/annotate/instructions.c b/tools/perf/arch/s390/annotate/instructions.c
index 8c72b44444cb..0a3e39b5143d 100644
--- a/tools/perf/arch/s390/annotate/instructions.c
+++ b/tools/perf/arch/s390/annotate/instructions.c
@@ -1,6 +1,57 @@
 // SPDX-License-Identifier: GPL-2.0
 #include <linux/compiler.h>
 
+static int s390_call__parse(struct arch *arch, struct ins_operands *ops,
+			    struct map *map)
+{
+	char *endptr, *tok, *name;
+	struct addr_map_symbol target = {
+		.map = map,
+	};
+
+	tok = strchr(ops->raw, ',');
+	if (!tok)
+		return -1;
+
+	ops->target.addr = strtoull(tok + 1, &endptr, 16);
+
+	name = strchr(endptr, '<');
+	if (name == NULL)
+		return -1;
+
+	name++;
+
+	if (arch->objdump.skip_functions_char &&
+	    strchr(name, arch->objdump.skip_functions_char))
+		return -1;
+
+	tok = strchr(name, '>');
+	if (tok == NULL)
+		return -1;
+
+	*tok = '\0';
+	ops->target.name = strdup(name);
+	*tok = '>';
+
+	if (ops->target.name == NULL)
+		return -1;
+	target.addr = map__objdump_2mem(map, ops->target.addr);
+
+	if (map_groups__find_ams(&target) == 0 &&
+	    map__rip_2objdump(target.map, map->map_ip(target.map, target.addr)) == ops->target.addr)
+		ops->target.sym = target.sym;
+
+	return 0;
+}
+
+static int call__scnprintf(struct ins *ins, char *bf, size_t size,
+			   struct ins_operands *ops);
+
+static struct ins_ops s390_call_ops = {
+	.parse	   = s390_call__parse,
+	.scnprintf = call__scnprintf,
+};
+
 static struct ins_ops *s390__associate_ins_ops(struct arch *arch, const char *name)
 {
 	struct ins_ops *ops = NULL;
@@ -14,7 +65,7 @@ static struct ins_ops *s390__associate_ins_ops(struct arch *arch, const char *na
 	if (!strcmp(name, "bras") ||
 	    !strcmp(name, "brasl") ||
 	    !strcmp(name, "basr"))
-		ops = &call_ops;
+		ops = &s390_call_ops;
 	if (!strcmp(name, "br"))
 		ops = &ret_ops;
 
diff --git a/tools/perf/util/annotate.c b/tools/perf/util/annotate.c
index 49ff825f745c..bc3302da702b 100644
--- a/tools/perf/util/annotate.c
+++ b/tools/perf/util/annotate.c
@@ -248,7 +248,7 @@ static struct ins_ops call_ops = {
 
 bool ins__is_call(const struct ins *ins)
 {
-	return ins->ops == &call_ops;
+	return ins->ops == &call_ops || ins->ops == &s390_call_ops;
 }
 
 static int jump__parse(struct arch *arch __maybe_unused, struct ins_operands *ops, struct map *map __maybe_unused)
-- 
2.14.3

Re: [PATCH v2] perf annotate: Fix s390 target function disassembly

[Arnaldo Carvalho de Melo]

Em Wed, Mar 07, 2018 at 02:43:25PM +0100, Thomas Richter escreveu:
> Perf annotate displays function call assembler instructions
> with a right arrow. Hitting enter on this line/instruction
> causes the browser to disassemble this target function and
> show it on the screen.  On s390 this results in an error
> message 'The called function was not found.'
> 
> The function call assembly line parsing does not handle
> the s390 bras and brasl instructions. Function call__parse
> expects the target as first operand:
> 	callq	e9140 <__fxstat>
> S390 has a register number as first operand:
> 	brasl	%r14,41d60 <abort>
> Therefore the target addresses on s390 are always zero
> which is an invalid address.
> 
> Introduce a s390 specific call parsing function which skips
> the first operand on s390.
> 
> Signed-off-by: Thomas Richter <tmricht@linux.vnet.ibm.com>
> ---
>  tools/perf/arch/s390/annotate/instructions.c | 53 +++++++++++++++++++++++++++-
>  tools/perf/util/annotate.c                   |  2 +-
>  2 files changed, 53 insertions(+), 2 deletions(-)
> 
> diff --git a/tools/perf/arch/s390/annotate/instructions.c b/tools/perf/arch/s390/annotate/instructions.c
> index 8c72b44444cb..0a3e39b5143d 100644
> --- a/tools/perf/arch/s390/annotate/instructions.c
> +++ b/tools/perf/arch/s390/annotate/instructions.c
> @@ -1,6 +1,57 @@
>  // SPDX-License-Identifier: GPL-2.0
>  #include <linux/compiler.h>
>  
> +static int s390_call__parse(struct arch *arch, struct ins_operands *ops,
> +			    struct map *map)
> +{
> +	char *endptr, *tok, *name;
> +	struct addr_map_symbol target = {
> +		.map = map,
> +	};
> +
> +	tok = strchr(ops->raw, ',');
> +	if (!tok)
> +		return -1;
> +
> +	ops->target.addr = strtoull(tok + 1, &endptr, 16);
> +
> +	name = strchr(endptr, '<');
> +	if (name == NULL)
> +		return -1;
> +
> +	name++;
> +
> +	if (arch->objdump.skip_functions_char &&
> +	    strchr(name, arch->objdump.skip_functions_char))
> +		return -1;
> +
> +	tok = strchr(name, '>');
> +	if (tok == NULL)
> +		return -1;
> +
> +	*tok = '\0';
> +	ops->target.name = strdup(name);
> +	*tok = '>';
> +
> +	if (ops->target.name == NULL)
> +		return -1;
> +	target.addr = map__objdump_2mem(map, ops->target.addr);
> +
> +	if (map_groups__find_ams(&target) == 0 &&
> +	    map__rip_2objdump(target.map, map->map_ip(target.map, target.addr)) == ops->target.addr)
> +		ops->target.sym = target.sym;
> +
> +	return 0;
> +}
> +
> +static int call__scnprintf(struct ins *ins, char *bf, size_t size,
> +			   struct ins_operands *ops);
> +
> +static struct ins_ops s390_call_ops = {
> +	.parse	   = s390_call__parse,
> +	.scnprintf = call__scnprintf,
> +};
> +
>  static struct ins_ops *s390__associate_ins_ops(struct arch *arch, const char *name)
>  {
>  	struct ins_ops *ops = NULL;
> @@ -14,7 +65,7 @@ static struct ins_ops *s390__associate_ins_ops(struct arch *arch, const char *na
>  	if (!strcmp(name, "bras") ||
>  	    !strcmp(name, "brasl") ||
>  	    !strcmp(name, "basr"))
> -		ops = &call_ops;
> +		ops = &s390_call_ops;
>  	if (!strcmp(name, "br"))
>  		ops = &ret_ops;
>  
> diff --git a/tools/perf/util/annotate.c b/tools/perf/util/annotate.c
> index 49ff825f745c..bc3302da702b 100644
> --- a/tools/perf/util/annotate.c
> +++ b/tools/perf/util/annotate.c
> @@ -248,7 +248,7 @@ static struct ins_ops call_ops = {
>  
>  bool ins__is_call(const struct ins *ins)
>  {
> -	return ins->ops == &call_ops;
> +	return ins->ops == &call_ops || ins->ops == &s390_call_ops;

This is good enough so far, but I think we may end up just making this
be:

bool ins__is_call(const struct ins *ins)
{
	return ins->ops->is_call;
}

This way we remove this arch specific stuff from the core annotate.c
code, applying this patch, this can be done on top, later.

- Arnaldo

[tip:perf/core] perf annotate: Fix s390 target function disassembly

[tip-bot for Thomas Richter]

Commit-ID:  0b58a77ca8792bd7798ef3a4d865c57694ec74fc
Gitweb:     https://git.kernel.org/tip/0b58a77ca8792bd7798ef3a4d865c57694ec74fc
Author:     Thomas Richter <tmricht@linux.vnet.ibm.com>
AuthorDate: Wed, 7 Mar 2018 14:43:25 +0100
Committer:  Arnaldo Carvalho de Melo <acme@redhat.com>
CommitDate: Thu, 8 Mar 2018 10:05:59 -0300

perf annotate: Fix s390 target function disassembly

'perf annotate' displays function call assembler instructions with a
right arrow. Hitting enter on this line/instruction causes the browser
to disassemble this target function and show it on the screen.  On s390
this results in an error message 'The called function was not found.'

The function call assembly line parsing does not handle the s390 bras
and brasl instructions. Function call__parse expects the target as first
operand:

	callq	e9140 <__fxstat>

S390 has a register number as first operand:

	brasl	%r14,41d60 <abort>

Therefore the target addresses on s390 are always zero which is an
invalid address.

Introduce a s390 specific call parsing function which skips the first
operand on s390.

Signed-off-by: Thomas Richter <tmricht@linux.vnet.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Link: http://lkml.kernel.org/r/20180307134325.96106-1-tmricht@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/arch/s390/annotate/instructions.c | 53 +++++++++++++++++++++++++++-
 tools/perf/util/annotate.c                   |  2 +-
 2 files changed, 53 insertions(+), 2 deletions(-)

diff --git a/tools/perf/arch/s390/annotate/instructions.c b/tools/perf/arch/s390/annotate/instructions.c
index 01df9d8303e1..e80589fc5b58 100644
--- a/tools/perf/arch/s390/annotate/instructions.c
+++ b/tools/perf/arch/s390/annotate/instructions.c
@@ -1,6 +1,57 @@
 // SPDX-License-Identifier: GPL-2.0
 #include <linux/compiler.h>
 
+static int s390_call__parse(struct arch *arch, struct ins_operands *ops,
+			    struct map *map)
+{
+	char *endptr, *tok, *name;
+	struct addr_map_symbol target = {
+		.map = map,
+	};
+
+	tok = strchr(ops->raw, ',');
+	if (!tok)
+		return -1;
+
+	ops->target.addr = strtoull(tok + 1, &endptr, 16);
+
+	name = strchr(endptr, '<');
+	if (name == NULL)
+		return -1;
+
+	name++;
+
+	if (arch->objdump.skip_functions_char &&
+	    strchr(name, arch->objdump.skip_functions_char))
+		return -1;
+
+	tok = strchr(name, '>');
+	if (tok == NULL)
+		return -1;
+
+	*tok = '\0';
+	ops->target.name = strdup(name);
+	*tok = '>';
+
+	if (ops->target.name == NULL)
+		return -1;
+	target.addr = map__objdump_2mem(map, ops->target.addr);
+
+	if (map_groups__find_ams(&target) == 0 &&
+	    map__rip_2objdump(target.map, map->map_ip(target.map, target.addr)) == ops->target.addr)
+		ops->target.sym = target.sym;
+
+	return 0;
+}
+
+static int call__scnprintf(struct ins *ins, char *bf, size_t size,
+			   struct ins_operands *ops);
+
+static struct ins_ops s390_call_ops = {
+	.parse	   = s390_call__parse,
+	.scnprintf = call__scnprintf,
+};
+
 static struct ins_ops *s390__associate_ins_ops(struct arch *arch, const char *name)
 {
 	struct ins_ops *ops = NULL;
@@ -14,7 +65,7 @@ static struct ins_ops *s390__associate_ins_ops(struct arch *arch, const char *na
 	if (!strcmp(name, "bras") ||
 	    !strcmp(name, "brasl") ||
 	    !strcmp(name, "basr"))
-		ops = &call_ops;
+		ops = &s390_call_ops;
 	if (!strcmp(name, "br"))
 		ops = &ret_ops;
 
diff --git a/tools/perf/util/annotate.c b/tools/perf/util/annotate.c
index 49ff825f745c..bc3302da702b 100644
--- a/tools/perf/util/annotate.c
+++ b/tools/perf/util/annotate.c
@@ -248,7 +248,7 @@ static struct ins_ops call_ops = {
 
 bool ins__is_call(const struct ins *ins)
 {
-	return ins->ops == &call_ops;
+	return ins->ops == &call_ops || ins->ops == &s390_call_ops;
 }
 
 static int jump__parse(struct arch *arch __maybe_unused, struct ins_operands *ops, struct map *map __maybe_unused)